Step 2: Grind the Surface

2. Grind the area that you heated. I use a flap-pad in an angle grinder, a wire wheel in an electric drill or an abrasive paint remover for this step. Do this outside. (Photo #1) The result is a bright and shiny steel surface (Photo #2 below the yellow line)
<p>Did he say in the &quot;meth lab section&quot;?</p>
<p>Or, follow Hackett's video to strip away galv, inside and out:</p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/8Tld3onsUVE" width="500"></iframe></p>
<p>Thanks for the video. I have been welding galvanized since its cheap and easily available. Hackett is a true genius and a real life MacGyver. For those of you that haven't seen his past tv show or videos, check them out. People like Hackett are why we have Instructables.</p>
sola0005, You can grind it off, but if it the galvanization done correctly, it actually seeps into the metal. The etching won't ever remove all of it, but it will be &quot;cleaner&quot; to weld. Fume wise, if you do get a mild bout of zink poisoning you can drink milk and it will minimize the nausea.
Any reason I couldn't skip the heating part and just grind the zinc coating off? <br>Thanks! <br>Susan
Most anythng galvanised can be welded using a stick welder and 316 stainless electrodes, there's no spatter or striking problems and an excellent weld is obtained. As usual, BEWARE OF THE FUMES!!
If using any acid to dissolve the galvanized coating, don't forget to wash the tubing well or the acid will keep working. Another option is to grind off the galvanized area you want to weld. As an extra precaution, buy a half face respirator like the 3M 3600 with 2097 filters. These fit well and can be used with practically any welding helmet.
I am guessing you are using a MIG welder. Do you need to weld in short bursts to avoid blowing holes in the tubing, or are you able to run a continuous bead? I have used a stick welder on EMT. The heat was about as low as I could go without sticking the rod. Starting an arc was difficult, so I used a piece of carbon rod. See <a href="https://www.instructables.com/id/Strike-an-arc-exactly-where-you-want-it-to-begin-/">my previous Instructable</a> on that. I used 1/16 inch 6013 rod and welded in short bursts. There was some grinding to be done afterward to make the welds look decent. For me, the difficult thing was to weld &quot;T&quot; joints like you have in your photo. The butted piece heats up faster at the end than the continuous piece does at the joint. It is very easy to blow holes.
i use a stick welder too 1/16 7018 works better though
A method I use is dipping the ends to be welded in Muratic acid. Yeah, the same stuff they use in pools. It etches the galv right off.
Thanks, I love this hint. I have some sort of acid around and it'll keep me from using up Mapp. Very cool.

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